1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2
3 #include <errno.h>
4 #include <stdio.h>
5 #include <unistd.h>
6
7 #include "generator.h"
8 #include "log.h"
9 #include "mkdir-label.h"
10 #include "string-util.h"
11 #include "util.h"
12
13 static const char *arg_dest = NULL;
14
15 /* So you are reading this, and might wonder: why is this implemented as a generator rather than as a plain, statically
16 * enabled service that carries appropriate ConditionFileIsExecutable= lines? The answer is this: conditions bypass
17 * execution of a service's binary, but they have no influence on unit dependencies. Thus, a service that is
18 * conditioned out will still act as synchronization point in the dependency tree, and we'd rather not have that for
19 * these two legacy scripts. */
20
add_symlink(const char * service,const char * where)21 static int add_symlink(const char *service, const char *where) {
22 const char *from, *to;
23
24 assert(service);
25 assert(where);
26
27 from = strjoina(SYSTEM_DATA_UNIT_DIR "/", service);
28 to = strjoina(arg_dest, "/", where, ".wants/", service);
29
30 (void) mkdir_parents_label(to, 0755);
31
32 if (symlink(from, to) < 0) {
33 if (errno == EEXIST)
34 return 0;
35
36 return log_error_errno(errno, "Failed to create symlink %s: %m", to);
37 }
38
39 return 1;
40 }
41
check_executable(const char * path)42 static int check_executable(const char *path) {
43 assert(path);
44
45 if (access(path, X_OK) < 0) {
46 if (errno == ENOENT)
47 return log_debug_errno(errno, "%s does not exist, skipping.", path);
48 if (errno == EACCES)
49 return log_info_errno(errno, "%s is not marked executable, skipping.", path);
50
51 return log_warning_errno(errno, "Couldn't determine if %s exists and is executable, skipping: %m", path);
52 }
53
54 return 0;
55 }
56
run(const char * dest,const char * dest_early,const char * dest_late)57 static int run(const char *dest, const char *dest_early, const char *dest_late) {
58 int r = 0, k = 0;
59
60 assert_se(arg_dest = dest);
61
62 if (check_executable(RC_LOCAL_PATH) >= 0) {
63 log_debug("Automatically adding rc-local.service.");
64
65 r = add_symlink("rc-local.service", "multi-user.target");
66 }
67
68 return r < 0 ? r : k;
69 }
70
71 DEFINE_MAIN_GENERATOR_FUNCTION(run);
72